1. Field
Embodiments of the present invention may relate to a device for transferring a cradle for use with a medical imaging equipment, and more particularly to a cradle transferring device for moving and withdrawing a cradle, on which a subject lies, to and from an examination table of an MRI apparatus in a PET-MRI hybrid system.
2. Background
A positron emission tomography (PET) apparatus and a magnetic resonance image (MRI) apparatus are widely used to obtain a brain image among medical imaging equipments. The MRI apparatus has the highest spatial resolution among the medical imaging equipments. The PET apparatus can provide various molecular images, which are difficult to be obtained by the MRI apparatus. Recently, “a PET-MRI hybrid system (or PET-MRI fusion image system)” has been developed in the art. The PET-MRI hybrid system can obtain high-resolution anatomic information and molecular information on a brain by integrating the PET apparatus and the MRI apparatus.
FIG. 1 shows a schematic constitution of the PET-MRI hybrid system. The PET-MRI hybrid system 10 provides fusion images on a brain by integrating the information obtained by the PET apparatus 11 and the information obtained by the MRI apparatus 12. The PET-MRI hybrid system 10 is provided with a cradle 13 (on which a subject lies) and a cart 14, which supports the cradle 13 and which is configured to reciprocate between the PET apparatus 11 and the MRI apparatus 12. This is so that the examination of a subject is carried out using a single system. The subject is located at the PET apparatus 11 and the MRI apparatus 12 by the cart 14 and each device carries out its examination. The fusion image of a brain is obtained based on the information obtained from each device.
A circular PET apparatus may be employed as the PET apparatus 11. The examination in the circular PET apparatus 11 can be carried out when the cradle 13 is moved in close proximity of the circular PET apparatus 11 and is then located in place where the examination can be carried out. The MRI apparatus 12 has a magnetic field tube 12a, which generates a magnetic field and carries out the examination, and an examination table 12b. Since the examination in the MRI apparatus 12 is carried out in the magnetic field tube 12a, the MRI apparatus 12 is configured such that the examination table 12b can be moved into and out of the magnetic field tube 12a. 
Accordingly, in order to construct the PET-MRI hybrid system comprising the PET apparatus and the MRI apparatus, a novel constitution must be provided, wherein the cradle 13 is moved to the examination table 12b of the MRI apparatus 12 for the examination in the MRI apparatus 12 and the cradle 13 is withdrawn from the examination table 12b of the MRI apparatus 12 after the examination in the MRI apparatus 12. Further, the examination table 12b of the MRI apparatus 12 is moved into and out of the magnetic field tube 12b as explained above. Therefore, there is a problem with a constitution wherein the cradle 13 is simply moved to the examination table 12b in that the cradle 13 cannot be accurately withdrawn from the examination table 12a after the examination in the MRI apparatus 12.